Renal agenesis results from defects in genes that regulate initial UB outgrowth such as Gdnf, Ret, and Gfra1. Also, the loss of certain genes, for example Eya1, Six1, Hox11, Wnt4, and Fgf8, which are involved later during metanephric development or nephron patterning, causes renal agenesis or hypoplasia [2]. This evidence concerns the gene WNT4 and renal agenesis.